Prime Minister Theresa May is battling to get her plan through Parliament despite the fact it suffered an historic defeat in the Commons last week - losing by 432 votes to 202.

Downing Street said it is continuing conversations with MPs to address a range of concerns about the backstop. The plan aims to keep an open Irish border after Brexit, when it becomes the UK's only land border with the European Union, by remaining aligned with certain EU rules.

Opponents of the backstop don't believe assurances that it will be be a temporary measure used as a last resort if no future trade deal is agreed with the EU.

They fear it will effectively trap the UK in the EU indefinitely, with no say over its rules and no ability to strike its own trade deals.